They are an important aid in monitoring immunotherapy. The quantification of allergen-specific IgG4 antibodies in serum provides an appropriate assessment of the immune response. IgG4 has the ability to regulate the immune response to the allergen and therefore has the potential to influence the clinical response.
Eosinophil cationic protein (ECP) is released from activated eosinophil granulocytes and is a marker of eosinophilic inflammation. High levels have been associated with active asthma and other allergic conditions.
ECP is a ribonuclease that has cytotoxic, neurotoxic, fibrosis and immunomodulatory properties. Regular ECP measurement can help keep asthma under control. It can help determine the severity of airway inflammation and helps determine the appropriate treatment in patients with asthma.
Tryptase is one of the main protein components secreted by mast cells when they are activated. Mast cell activation may be due to either allergy or anaphylaxis, or may be the result of mastocytosis (dermal or systemic) or haematological neoplasms.
Measurement of serum tryptase helps to identify the cause of the allergic symptoms and whether it is a pure allergic reaction or mastocytosis. It is also a risk factor for patients who have severe anaphylactic reactions, especially after an insect bite, and determines whether immunotherapy will be effective. Finally, it is used as a clinical marker in severe reactions during surgery, due to possible sensitisation to an administered substance.
A simple blood draw is required to measure tryptase. In our laboratory, tryptase is determined in serum using Phadia’s ImmunoCAP method, which is the most reliable method.